When the Core Design copyright screen appears, press Up, Down, Left, Right, Down(2), Right(2), Square in the NTSC version of the game. For the PAL version of the game, press Triangle instead of Square. If you entered the code correctly, a debug menu will appear. Highlight the credits option in the debug menu and press Left(8), Triangle for an added bonus.
Start a game and then press Start + Select to quit. Then at the main title screen, press Up(3), Down(3), Right(2), Triangle. If you entered the code correctly, you will hear the sound of a chime. While playing the game, the energy bar will still go down, but will eventually rise again.
Enter the briefing area and go to the locker on the left side of the screen. Then, open the locker and enter "4L2CZCQKDAABACQDB" at the password screen. Now a mission to destroy the Crimson Blade training camp in the Masirah Mountains will begin.
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